Abstract P1-01-14: Intraoperative Injection of Technetium-99m- Dextran 500 for the Identification of Sentinel Lymph Nodes in Breast Cancer

Abstract

Abstract Background: The intraoperative injection of radiocolloid before a sentinel node biopsy (SLN) in breast cancer has been recently described.The advantages of this approach would be precluding the performance of a scintigram, cost reduction and elimination of pain and anxiety related to the preoperative procedure. Objectives: To evaluate the efficacy of intraoperative injection of Dextran 500-99m-Tc and to analyze whether different radiocolloid doses, breast volume and Body Mass Index (BMI) influence the migration time to the axilla. Material and Methods: This is a prospective study of 74 SLN biopsies of breast cancer patients, stages T1N0 and T2N0. After anesthesia induction, patients underwent subareolar dermal injection of 0.5 to 1.5 mCi (18 to 55 MBq) of filtered Dextran 500-99m-Tc (0.22µl) in a volume of 5 ml along with 2 ml of blue dye. Results: The probe identification rate was 98% (73/74 cases) and the medium radiocolloid dose used was 0.97 mCi ± 0.22. The radiocolloid migration time to the axila was 10 min and 43 s (± 5:43 s). An average of 1.66 lymphnodes were identified through the use of radiocolloid and 1.53 through the use of bue dye. Different radiocolloid doses did not modify migration time to SLN (p=0.73). However, larger breast volumes were associated with longer migration time to the axilla (Pearson Correlation 0.393 p< 0.01). The same correlation was observed with BMI (Pearson Correlation 0.469 p< 0.01). Discussion: The intraoperative injection of Dextran 500-99m-Tc is efficient in the identification of SLN in breast patients. Higher BMI and larger breasts determine longer migration time, however injection of larger doses of radiocolloid do not reduce transit time to the axilla. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-01-14.